At around the 64° 45’N parallel a shift is found between the East Volcanic Zone and the North Volcanic Zone. The zones are connected at the Kverkfjöll area, but south of there the volcanic systems trend NE-SW, whereas north of there the NS alignment is obvious. Looking at the grid formed by convection division lines, this becomes more understandable. Along this parallel the grid is transformed from being composed of large and regular diamond shaped polygons south of the line, into the rather complex matrix of much smaller polygons. The overall match between volcanic zones and convection cell grid is obvious. The relevant lines are drawn on a map from Náttúrufræðistofnun:

Published by Steingrimur Thorbjarnarson
I am a geologist, graduated from the University of Iceland, and taught geology for a few years. I have gained some knowledge about Earth's inner structure, so I provide this website as my contribution to answer one of the greatest questions remaining within the realm of geoscience. Experiments show that the mantle should form convection rolls when close to the melting point. I took this literally, and calculated the dimensions and shape of these mantle convection rolls. Then I compare that model with the surface. This makes it possible to provide many interesting examples about geology found on my blog.
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